1. A. Inventory Variations.

   1. (1) An owner and an operator of a UST system shall review the reconciled inventory records required by COMAR 26.10.04.01 for the following:

      1. (a) Inventory variations exceeding 1 percent plus 130 gallons of the metered quantity of a regulated substance each calendar month; and
      2. (b) Daily inventory records that show 7 consecutive days of shortage totaling 80 gallons or more.

   2. (2) An owner and an operator of a UST system shall conduct a review of reconciled inventory records at the following frequencies:

      1. (a) Review inventory variation as required under §A(1)(a) of this regulation monthly; and
      2. (b) Review daily inventory records as required under §A(1)(b) of this regulation daily.

   3. (3) Reporting and Investigating Inventory Variations.

      1. (a) An operator of a UST system shall report a variation or shortage as described in §A(1) of this regulation to the owner of the UST system;
      2. (b) Upon discovery of an inventory variation, an owner and an operator of a UST system shall immediately investigate the cause of the variation or shortage;
      3. (c) If the investigation required under §A(3)(b) of this regulation reveals no indication of a discharge or release from a UST system, an owner and an operator of a UST system shall state the cause of the inventory variation or shortage in the daily inventory records; and
      4. (d) If the investigation required under §A(3)(b) of this regulation reveals a discharge or release from a UST system, an owner and an operator of a UST system shall follow the procedures established under COMAR 26.10.08.

2. B. The Department may require an owner and an operator of a UST system to perform a precision tightness test of the UST system:

   1. (1) If the owner and the operator fail to reconcile daily inventory records as specified in COMAR 26.10.04.01 and review the reconciled records in accordance with §A of this regulation;
   2. (2) If the owner and the operator fail to comply with monthly release detection requirements of Regulation .05 of this chapter; or
   3. (3) For any other good cause as determined by the Department.
3. C. The Department may require an owner and an operator of a UST system to perform a precision tightness test of the UST system and install monitoring wells or conduct a site assessment if there is reason to believe there is or may have been a discharge or release of a regulated substance from the UST system.

Authority: Environment Article, §§4-401, 4-402, 4-405, 4-407—4-411.2, 4-415.1, 4-417, 4-701 et seq., and 7-201 et seq., Annotated Code of Maryland

Effective date: February 4, 1991 (18:2 Md. R. 151)

Chapter revised effective November 4, 1996 (23:22 Md. R. 1498)

Regulation .01 amended effective February 18, 2002 (29:3 Md. R. 224)

Regulation .01A amended effective January 12, 2009 (36:1 Md. R. 25)

Regulation .02B amended effective June 29, 1998 (25:13 Md. R. 997)

Regulation .02C amended effective January 16, 2006 (33:1 Md. R. 39)

Regulation .02D amended effective January 12, 2009 (36:1 Md. R. 25)

Regulation .04 amended effective January 12, 2009 (36:1 Md. R. 25)

Regulation .04B amended effective June 29, 1998 (25:13 Md. R. 997)

Regulation .04C amended effective February 18, 2002 (29:3 Md. R. 224); January 16, 2006 (33:1 Md. R. 39)

Regulation .06 amended effective January 16, 2006 (33:1 Md. R. 39)

Regulations .01—.06 repealed and new Regulations .01—.06 adopted effective June 13, 2022 (49:12 Md. R. 642)